1. Field
Exemplary embodiments of the present invention relate to a variable resistance memory device and a method for fabricating the same, and more particularly, to a variable resistance memory device, which includes a variable resistance layer capable of electrical resistance changed by migration of vacancies or ions or phase change of a substance, and a method for fabricating the same.
2. Description of the Related Art
A variable resistance memory device refers to a device which stores data, based on such a characteristic that resistance changes according to an external stimulus and switching is implemented between two different resistance states. The variable resistance memory device includes a resistive random access memory (ReRAM), a phase change RAM (PCRAM), and a spin transfer torque-RAM (STT-RAM). The variable resistance memory device has been researched because of a simple structure and various excellent properties such as nonvolatility and so forth.
Meanwhile, in order to improve the integration degree of the variable resistance memory device, the so-called cross point cell array structure has been suggested. The cross point cell array structure refers to a structure including memory cells disposed at crossing points between a plurality of bit lines extending in a direction and a plurality of word lines extending in another direction crossing with the bit lines.
However, in order to form the cross point cell array structure, a plurality of mask processes should be repeated to pattern the bit lines and the word lines to a minimum critical dimension. Further, processes for a cell region and a peripheral region should be separately performed. Accordingly, fabrication processes may be complicated, and the fabrication costs may increase.